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Boric Acid Facts


In this article, we will give you some boric acid (hydrogen borate) information – the chemical formula is (H 3 BO 3) – and answer questions such as what boric acid is used for and where Boric acid crystals come from.

Let’s get started!

What is Boric acid?

Boric acid (H 3 BO 3) can also be known as boracic acid, hydrogen borate (BO 3), and orthoboric acid. Boric acid is a weak acid, Boric acid powder is white and looks similar to baby powder, and it can be in the form of colorless crystals that are tasteless. The colorless crystals dissolve in water.

Boric acid is not toxic when in small amounts that occur naturally. It exists in all plants, vegetables, grains, nuts, fungi, and almost all fruit. You don’t notice it because boric acid crystals are tasteless.

The chemical name is H 3 BO 3, and often written as B(OH)3; it contains the elements Boron oxides, oxygen, and hydrogen. When occurring in this form, it is a mineral, and it is called Sassolite. Its full uses are in the Merck index, an encyclopedia of chemicals and drugs. Boric acid is made from the same chemical compounds as borax, even looking very similar.

Metaboric (HBO2) and Pyroboric (H 2 B 4 O7) and Boric oxide (B2O3)



The water in Boracic acid is lost when heated, and it changes into different compound, metaboric acid (HBO2), and then becomes pyroboric acid (H 2 B 4 O7). Only when pyroboric acid (H 2 B 4 O7)  is heated over 300 centigrade does it become Boric oxide (B2O3). The three are hydrates of Boric acid (B2O3). Orthoboric acid is soluble in water.

In summary

  • Boric acid is known as Orthoboric acid, Hydrogen orthobrate, and Boracic acid. Inorganic borates convert to Boric acid.

  • Elements of Boric acid are Hydrogen, Boron, and Oxygen.

  • The chemical formula of Boric acid, H 3 bo 3

  • Toxicity, Boric acid is toxic if consumed.


It is also known as Sodium tetraborate and comes in the form of white mineral powder crystals. Its crystals give it a solid structure that is symmetrical due to its unique molecule pattern.

It has been used for many years now to clean things. Boron compounds are also useful for cleaning mold and mildew around the home.

It is a great solution and is most commonly used as a pesticide for getting rid of ants, cockroaches, mites, and spiders and for killing insects like wood-eating termites. Sodium tetraborate will not kill ticks or aphids.

You can make your own pesticide using it; just mix some of the borax powder with honey to make a paste and put it in areas you need it to work. The paste does a really good job of getting rid of the pests around the home.

It can be used to protect the wood and works as a flame retardant if a solution is applied to the wood. You can buy borate rods to put into the wood, and the chemical will then penetrate and treat that wood. This technique is used to protect ancient ships and buildings.

It is also used in flame retardants. When applied to surfaces, it will prevent smoldering, glowing, and smoke. This is because Boric acid releases water, resulting in char forming on the surface.

Borax is commonly used as a detergent booster for laundering clothes, as the white powder is able to remove tough stains. It is not related to bleach and does not contain bleach, although people do add them together for greater cleaning powers. It can be found in toothpaste, soaps, and for teeth bleaching.

Like Boric acid, it is used during production to make ceramics, glass, and pottery.

It is commonly used as an herbicide. It can be used in the garden to get rid of weeds if it is sprinkled around the weeds and left to do its job.


Boric acid is an acid of Boron; its salts are called borates. Boric acid and its sodium salts are pesticides found naturally around us.

Plants need Boron, the main compound of Boric acid, to grow. Too much, however, can be toxic and can affect the plant’s growth.

Recent data has found that the average intake of boron is 1.0 and 1.28 mg boron per day. In these small, naturally occurring amounts of boron, it is not harmful.

Boron is made by treating borax with hydrochloric acid (na 2 b 4) and crystallizing out the boric acid.

Boron dissolves in water. Boron can be removed from water with filtration using an anion exchanger.

Boron can be found in crop fertilizers and is used for soil lacking in Boron. Plants and crops grow better in soil with Boron present in it. It is applied to the surface of the soil, and once wet, it will dissolve its compounds into the soil. The roots of the plants or crops will take in the Boron, which will help them grow taller.

When Boric acid is heated, the chemical produced is called Pyroboric acid (b 4 o 7).

Boric acid is found in the following:

Boric acid B (OH)3 is used mainly with pesticides; it can be purchased in many forms, as powder, liquid or tablet, gel, paste, pellets, and aerosols.

Boric acid can be found in many products added during the manufacture of cleaning products. These might be used in homes, industrial factories, sewers, and hospitals.

  • Boric acid is also found in insecticides and is used for pest control, herbicides, or found in fungicides used to control fungi and mold. Boric acid will kill ants, fleas, silverfish, termites, or cockroaches and is very effective.

  • Boric acid has been used to preserve foods because it has been effective against yeasts as early as the 1870s. Countries began to make it illegal to put Boric acid in foods due to high levels of it being used, and food was found to contain too much to be safe to consume. In the United States, the food and drug administration has banned it as a food additive.

  • Boric acid is also used for wood preservatives and glass and is also used as a flame retardant. Boric acid is used as a fire retardant, as it has the ability to release water.

  • Boric acid is used on many products like roofing membranes, electronics, appliance components, textile fiberglass, fabric, upholstery, mattresses, and wall coverings to keep people safe.

  • Boric acid is also used in artificial gems, printing, tanning, impregnating wicks, and electric condensers, and hardening steel.

  • Boric acid is effective at getting rid of fleas by applying somewhere flea eggs have been found and then leaving it to work.

  • Aqueous solutions of Boric acid are used to remove pollutants like smog and pollen.

  • Boric acid is the predominant form used in spas and swimming pools, and sewage systems.


It was discovered that Boric acid, which is a very weak acid, has properties that could act as an antiseptic in a variety of consumer products.

  • Boric acid is also used in the manufacture of medicine and can be present in the medical treatment of yeast infections and mild antiseptics that are applied topically.

  • Due to its mild antiseptic properties, it is for external use to control bacteria, such as those that cause athlete’s foot. Boric acid can be absorbed through intact skin and damaged skin.

  • Boric acid is used for symptoms of recurrent vulvovaginal candidiasis.

  • Mixed as a very dilute solution, Boric acid can be used as an effective eye wash. It can also be used to treat burns and cuts on the body surface as it is readily absorbed through the skin and mucous membranes. It is also used in emergency medicine.

  • Boric acid and other Borates are also used in over-the-counter supplements.

LCD Televisions



Boric acid is used to make the glass for high-tech LCD flat panel displays. It enhances the glass properties under extreme manufacturing conditions, resulting in a higher quality product.


Boric acid is used in the production of glasses, including borosilicate (heat-resistant glass). Boric acid increases the chemical and temperature resistance of glass.

Around 10-20 % of glassmakers add boric oxide to the silica base, and these compounds will lower the melting temperature of the glass. Boric acid is used in the making of fiberglass and halogen light bulbs.

Pyrex is a well-known make-in kitchens. It contains Boric acid, which can make them up to 5 times stronger than glass due to the chemical and temperature resistance of Boric acid. Pyrex glass dishes can cope with temperatures up to 425 degrees Fahrenheit, making them great for use in cooking.

Where does Boric acid come from?

Boric acid can be found in its natural form at the sites of volcanoes and hot springs and can occur in the dry salt lakes of Nevada and California. This is where it appears in the form of the mineral sassolite.

Boric acid naturally occurs

Boric acid naturally occurs in plants, soil, and water because it is soluble it can travel through the soil. Boric acid can also be brought out by plants growing in the soil.

Boric acid is naturally present in most fruits, vegetables, and grains. Children and adults are probably eating Boric acid every day in their food and water and not knowing it, as Boric acid crystals are tasteless and do not have an odor.

How does it kill pests?

Boric acid also works to control insects as an insecticide. The insects walk over the white powder, and this is then absorbed into their body, which damages the insect’s stomach and nervous system. If insects eat the Boric acid, it has the same effect on the stomach, poisoning the pests. Boric acid can also damage the exoskeleton of the pest.

Boric acid B(OH)3 and Borax (sodium tetraborate decahydrate) can also kill plants, as it stops the growth of the plants. It is a sodium borate salt that will dry out the plants.

Acute Boric acid poisoning

Boric acid B(OH)3 is low in toxicity, as borax (a sodium borate salt), can damage the eyes and irritate the skin. If eaten, Boric acid commonly can make people feel nauseous and actually be sick, and it can cause diarrhea, stomach pains, weight loss, and a skin rash. This can be followed by rashes, lack of energy, and weakness.

Call your local Poison Control Center if you would like to discuss a pesticide problem.

In high doses, being consumed or long-term exposure or consumption, according to clinical toxicology reports, can lead to the death of an unborn child, coma, liver and kidney problems, damaged fertility, and eventually liver and kidney failure. Therefore it is best to keep exposure and consumption of Boric acid as low as possible.

Exposure to Boric acid, Orthoboric acid, hydrogen borate

Due to a lack of data, it is not clear if infants are more sensitive to Boric acid than adults. Children play and explore, which could put them at greater risk of exposure to Boric acid. When using Boric acid, it should be in use out of the reach of children so they do not come into contact with it.

Long term exposure is not a good idea.

If infants were to eat 5 grams of Boric acid, it could cause death. Ingestion of 15-20 grams could cause death in adults. According to the EPA, laboratory animals exposed to Boric acid did not have any signs of cancer.

Boric acid was once commonly used in the production of talcum and was present in infant diaper powders to ease rashes due to its antibacterial properties. This compound was banned, as it was deemed that if it enters the body through an injury, it is too toxic and could cause harm.

Is Boric acid safe for fish, birds, and other animals?

Boric acid is commonly found naturally in soil, water, and plants. It is not toxic to birds and only slightly toxic to pond animals such as fish and frogs.

The EPA (Environmental Protection Agency) has stated that during tests, Boric acid is practically non-toxic to bees. During tests, syrup fed to bees containing 50mg of Boric acid did not harm them at all. Large amounts containing over 100mg of Boric acid killed the bees.

And finally,

We hope you have found the information relating to ‘Boric acid facts’ in this article helpful. Did you realize Boric acid was used for so many different things?

Should you have any questions, please do not hesitate to contact us by dropping an email. We do our best to respond as soon as possible. 

Ronald has 25 years of pest control experience under his belt. He scrutinizes each control method, product and process to prevent infestations effectively. 

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